Sulfidic caves in Albania – hotspots of subterranean biodiversity

Unusually abundant and diverse invertebrate communities comprising numerous endemic species have been discovered in sulfidic subterranean ecosystems in Romania, Italy, Israel, Greece, Iran, Russia, and more recently in Albania. In these hypogean environments, chemoautotrophic sulfur- and methane-oxidizing-, and nitrifying microorganisms use the redox interface between the reduced chemical compounds in the sulfidic aquifers, and the dioxygen in the cave atmosphere to generate copious amounts of trophic resources in situ. In this study we present the results of recent investigations performed in four distinct karst regions in Albania, where sulfidic subterranean lakes and streams have been discovered in limestone caves: Zalles Cave (North of Tirana), Avulit Cave (in the Holtas Canyon), Dragon’s Breath Cave (in the Langarica Canyon) and the Vromoner Karst Sytem - located in the Sarandaporo Valley, on the border between Albania and Greece. Several endemic species of amphipods (3), ostracods (2), terrestrial isopods (6), centipedes (1), scorpions (1), spiders (2), pseudoscorpions (6), and collembola (2) are being studied at the moment. Stable isotope and radio-carbon (¹⁴C) measurements enabled us to identify the food sources for the cave invertebrate communities, and to determine the structure of the subterranean food-webs. Our results are shared with local authorities providing them with reference data to be used in conservation actions aimed at biodiversity preservation in Albania.